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Hermann J. Muller - Biographical

Hermann
Joseph Muller was born in New York City on December 21, 1890.
His grandparents on his father's side were of artisan and
professional background and, though at first Catholics, had
emigrated from the Rhineland during the wave of reaction of 1848
to seek the greater freedom of America. His father, born in New
York, had continued the grandfather's art metal works (the first
in the U.S.A.), but was not by inclination a business man, and,
although he died in 1900, he early awoke in the boy a lively
interest in the nature of the universe and in the process of
evolution, as well as in the welfare of men in general. The boy's
mother, Frances Lyons Muller, had also been born in New York
City. Her parents had come from Britain, but were in the main
descended from Spanish and Portuguese Jews who, as an
after-effect of the Inquisition, had settled generations earlier
in England and Ireland. She, as well as the father, encouraged in
the boy a broad sympathy, an interest in living things, and a
love of nature.

He was brought up in Harlem, first attending public school there
and later Morris High School (also public) in the Bronx. There he
and his classmates Lester Thompson and Edgar Altenburg founded
what was perhaps the first high-school science club. Though his
family (mother, sister Ada, and himself) had very limited means,
they were fortunate in usually being able to spend their summers
in the country while he was of school age. But he was enabled to
attend a first class college - Columbia - only through the unexpected award of a
scholarship (the Cooper-Hewitt), automatically granted to him in
1907 on the basis of entrance examination grades. He spent his
summers, during his college years, at such jobs as bank runners
and hotel clerk (the latter at $25 a month, plus board, for a
14-hour work-day).

At Columbia College he was before the end of his first year
fascinated by the subject of biology. Reading by himself in the
summer of 1908 R.H. Lock's (1906) book on genetics, his interests
became centered in that field. Courses soon afterwards taken
under E. B. Wilson influenced him profoundly, as did also his
reading, independently of courses, of works by Jacques Loeb and
by other writers on experimental biology and physiology. In I909
he founded a students' biology club, which was participated in,
among others, by Altenburg, and by two students, Bridges and
Sturtevant, who had entered Columbia a year later.

For his first two years of graduate work, since there was no
opening offered to him in zoology, he managed to obtain a
scholarship (1910-1911) and then a teaching fellowship
(1911-1912) in physiology, the latter at Cornell Medical
College, while keeping up with genetics on the side and doing
various extra jobs, such as teaching English to foreigners in
night school. Finally, however, he obtained a teaching
assistantship in zoology at Columbia (1912-1915). The first
summer (1911) of graduate work was spent in studies at Woods
Hole, the rest in laboratory teaching at Columbia. During these
five years he was seriously overworked. In all this period he was
chiefly interested in the Drosophila work which Morgan had opened up, and from 1910 on
he closely followed this research and was an intimate member of
the group, although he did not have opportunity for much
experimental work of his own on this material until 1912. Then he
was able to begin his investigation of the simultaneous
inter-relationships of many linked genes, which supported the
theory of crossing-over and constituted his thesis. At the same
time he undertook his analysis of variable, multiple-factor,
characters by means of the device of «marker genes».
This extended the validity both of chromosomal inheritance and of
gene stability, and led later (1916) to his theory of balanced
lethals.

Called to the Rice Institute, Houston, as Instructor, by Julian
Huxley, he taught varied biological courses (1915-1918), and
began studies on mutation. During this time and the two years
following, when he was again at Columbia (1918-1920), now as
instructor, he elaborated methods for quantitative mutation
study. Altenburg, who had meanwhile moved to the Rice Institute,
and he, partly in collaboration, obtained the first results in
this field (1918-1919), including evidence that made probable an
effect of temperature. He then (1920) returned to Texas, this
time to the University, at Austin, as Associate Professor, and
from 1925 on as Professor, teaching mainly genetics and
evolution, and doing research mainly on mutation. He formulated
in 1918, 1920, 1921, and 1926 the chief principles of spontaneous
gene mutation as now recognized, including those of most
mutations being detrimental and recessive, and being point
effects of ultramicroscopic physico-chemical accidents arising in
the course of random molecular motions (thermal agitation). At
the same time he put forward the conception of the gene as
constituting the basis of life, as well as of evolution, by
virtue of its possessing the property of reproducing its own
changes, and he represented this phenomenon as the cardinal
problem of living matter.

In late 1926 he obtained critical evidence of the abundant
production of gene mutations and chromosome changes by X-rays
(published 1927). This opened the door to numerous researches,
many of them carried on with the aid of students and co-workers,
both at his own and other institutions, in the twenty years that
followed. These have been briefly outlined in his Nobel Lecture,
since they, together with the first discovery of the effect,
constitute the work for which the Nobel Award was granted. They
include studies on the mechanisms of the gene mutation effects
and of the structural changes, on the roles which each kind of
changes, when spontaneously occurring, play in evolution, and on
the properties of genes and of chromosome parts (e.g. eu- versus
hetero-chromatin), as disclosed by studies in which the
chromosomes were broken and rearranged.

This later work was carried on at a succession of places. In 1932
he was awarded a Guggenheim Fellowship and for a year worked at
Oscar Vogt's institute in Berlin, in Timoféeff's department
of genetics. At the request of N. I. Vavilov, he then spent 3 1/2
years as Senior Geneticist at the Institute of Genetics of the
Academy of Sciences of the U.S.S.R., first in Leningrad later
(1934-1937) in Moscow, with a considerable staff of co-workers.
With the rise of the Lysenko anti-genetics movement, he moved to
the Institute of Animal Genetics, University of Edinburgh (1937-1940); here
numerous graduate students, largely from India, took part. Then,
from 1940 to 1945, I he did both teaching and research at
Amherst
College, being professor ad I interim there from 1942 to
1945. At Amherst he completed a large-scale experiment showing
the relationship of ageing to spontaneous mutations. Finally, in
1945, he accepted a professorship in the Zoology Department at
Indiana
University, Bloomington, Indiana. Here he is again devoting
his time chiefly to work on radiation-induced mutations, using
them on the one hand for purposes of genetic analysis and on the
other hand in the study of how radiation produces its biological
effects.

One group of studies, participated in by J. I. and Ruby M.
Valencia, I. H. Herskowitz, I. I. Oster, S. Zimmering, S.
Abrahamson, A. Schalet, J. D. Telfer, Helen U. Meyer, Sara Frye,
Helen Byers, and others, has been concerned with the influence on
mutation frequency in the fruit fly Drosophila of diverse
conditions and agents, when these were used before, after, or
with radiation, or without radiation, on the influence of
dose-rate and total dose of the radiation, and on the relative
sensitivities of different cell stages to induced or natural
mutagenesis. The types of mutations studied included
«point» changes and both minute and gross structural
changes of chromosomes. In another group of studies, since
carried much further by E. A. Carlson, the interrelations among
independently arisen mutations of the same gene were studied
intensively, their intra-genic arrangement determined, and
principles governing their functional interactions worked
out.

The incidence of radiation damage to the bodies of the
individuals that have themselves been exposed, as manifested in a
long-term mortality or, in other words, life-span shortening or
accelerated «ageing», was also investigated, first by
I. I. Oster and then by W. Ostertag and Helen U. Meyer in
collaboration with Muller. Evidence was obtained that these
effects are for the most part consequences of losses of
chromosomes from dividing somatic cells, after these chromosomes
have been broken by the radiation. Natural ageing, however, gave
evidence of not being caused in this way.

Another group of researches, also carried out with cooperation
from students, more especially Margaret Lieb and S. L. Campbell,
had concerned itself with problems of dominance and related
subjects. It was shown that most mutant genes are incompletely
recessive (not «overdominant») and are acted upon by
selection while heterozygous. Studies of dominance in relation to
«dosage compensation» disclosed that selection usually
acts with high precision, tending to establish homozygous
«normal» types. Most genetic variation within
populations was deduced to depend on the recurrence of
detrimental mutations which, balanced by selective elimination,
constitute a «load». Estimates of this load were formed
for both Drosophila and man (in the latter case in
cooperation with Drs. Newton E. Morton and James F. Crow of the
University of Wisconsin).

Included in the studies were calculations concerned with both the
«spontaneous» and the radiation-induced mutation
frequencies, and of the consequences of selection. Estimates were
made of the effects of changes in mutation frequency, on the one
hand, and of selection pressure, on the other hand, on the load.
It was shown that eugenic policies are needed to avoid genetic
degeneration in man as well as to bring about the genetic
enhancement called for by his advances in technology and in other
aspects of his culture. It was pointed out that modern
reproductive technologies, such as germ-cell banks, and
liberalized mores now make possible the exercise of voluntary
germinal choice in human reproduction, and that this procedure
affords the practical solution necessary to enable cultural
evolution to promote the biological evolution of man instead of
perverting it.

Prof. Muller will retire from Indiana University, in June, 1964,
to take an appointment at the Institute for Advanced Learning in
the Medical Sciences, The City of Hope, Duarte, California - for
one year.

Muller has contributed over 300 articles on biological subjects
to the scientific publications of learned societies. His
principal books are The Mechanism of Mendelian Heredity
with T. H. Morgan and others, 1915 and 1922, Out of the Night
- a Biologist's View of the Future, 1935, 1936, and 1938, and
Genetics, Medicine and Man with C. C. Little and L. H.
Snyder, 1947.

He was President of the 8th International Congress of Genetics in
1948 and of the American Humanist Association during
1956-1958. He has received Doctor of Science degrees from the
Universities of Edinburgh (1940), Columbia (1949)
and Chicago (1959), the
honorary Doctor of Medicine from Jefferson
Medical College (1963), the Annual Award of the American
Association for Advancement of Science (1927), the Kimber
Genetics Award (1955) and the Darwin-Wallace Commemoration Medal
(1958). He was Pilgrim Trust Lecturer (Royal Society) and
Messenger Lecturer (Cornell University) in 1945, and was
designated Humanist of the Year by the American Humanist
Association in 1963. He has also received honorary memberships
and fellowships of many learned societies in the United States,
England, Scotland, Sweden, Denmark, India, Japan, Italy,
etc.

Muller married his first wife, formerly Jessie M. Jacobs, in 1923
- they had one son, David Eugene. In 1939 he married Dorothea
Kantorowicz - they have one daughter, Helen Juliette.

This autobiography/biography was written
at the time of the award and first
published in the book series Les
Prix Nobel.
It was later edited and republished in Nobel Lectures. To cite this document, always state the source as shown above.